packets Loss in nRF51 & iOS streaming.

[Bayram ZAYET]

Hello NORDIC community,

I am performing a BLE throughput speed test via an example of streaming a buffer of 2500 bytes per second: This says a sending frequency of 19 Kbps.

I'm working on an iPhone 6s with a version of iOS: 10.3.2 Since the connection interval is 30ms (the minimum value supported by an iPhone). The sending and receiving frequency is 31 Kbps: for the value of 6 packets per connection interval. this stream should be working fine.

==> the result of my tests shows considerable losses !!!

I wanted to know if my problem results from my module nRF51 or the iPhone?

Am I missing a parameter in my calculations ?

If possible, is the number of packets per connection interval on an iPhone 6s with an iOS: 10.3.2 really 6 or less?

Thank you in advance for your reactivity.

Best Regards,

[run_ar]

Are you transfering data from iOS to nRF51 or the other way around? If you are transfering data from iOS to nRF51 using write without response it is possible to overwrite the tx buffers on the iOS side. If you are transfering data from nRF51 to iOS it is not possible to overwrite the tx buffers. instead you will get an error message when calling the hvx function. Please make sure you check this and try again when you get the tx-complete event in case there are no available tx buffers.